STS prepaid metering: a buyer’s guide
STS defines secure messages between a vending system and a payment meter. Buying an STS-capable meter also requires decisions about the vending system, keys, operator processes and the exact certified configuration.
Reviewed 11 October 2026 · AFMETER
Credit and management tokens have different jobs
Credit tokens add the purchased units. Management tokens can perform authorised configuration operations, including key changes. The meter and vending system must be configured to work together.
Specify the operational responsibilities
Ask who controls the supply group, keys, vending access and meter commissioning. Define the key-change process, meter replacement workflow and support route for rejected tokens. Do not publish generic reset codes as if they work for every meter.
Test your actual purchase and recharge workflow
Use a sample configuration and the proposed vending platform. Verify a purchase, credit loading, a power interruption and reconciliation. Agree error handling and the operator’s instructions before deployment. Token acceptance depends on the meter’s state and configuration; a blanket expiry statement is not a reliable troubleshooting rule.